The present invention relates to a pedal stroke sensor attachment structure of an automotive vehicle, and specifically, relates to the pedal stroke sensor attachment structure of the automotive vehicle which comprises a falling-off mechanism configured to make a pedal rotational axis fall off a support portion of the pedal rotational axis when a collision load to make a pedal retreat toward a passenger side is applied to a vehicle body.
In general, an automotive vehicle has a pedal device, which is provided at a vehicle body positioned in front of a driver's seat, such as a dash panel, and comprises a bracket attached to the vehicle body and a hanging-type pedal supported at the bracket via a pedal rotational axis. In recent years, the vehicle, in which a falling-off mechanism to make the pedal fall off the bracket when the dash panel is moved in a vehicle collision and the bracket retreats is provided to protect passengers against the vehicle collision, is known. Further, there is a case in which a pedal stroke sensor comprising a detecting element to detect a swinging stroke of the pedal is provided at the pedal device.
Conventionally, in a case in which both the falling-off mechanism and the stroke sensor are provided at the pedal device, the stroke sensor is offset-arranged above or forward relative to the pedal rotational axis so as to avoid any interference with the pedal which falls off, and the pedal rotational axis and the stroke sensor are connected via a link mechanism, such as a link arm. However, it is necessary to provide an arrangement space of the stroke sensor. Further, there is a structure in which the stroke sensor is provided coaxially with the pedal rotational axis in place of the offset-arrangement of the stroke sensor relative to the pedal rotational axis.
Herein, in the former where the link mechanism is used, there is a case in which a stroke of the pedal and a stroke of the sensor do not synchronize. That is, there is a problem in that there exits a difference between a pedal-stroke angle and a sensor angle, so that the stroke sensor and a control program which are designed for being coaxial may not be used simply. Thus, there is a room for improvement.
Meanwhile, in the latter where the stroke sensor is arranged coaxially with the pedal rotational axis, there is a concern that because an attachment portion where the pedal bracket pivotally supporting the pedal is attached to the vehicle body via an attaching member, such as a bolt and nut, and the stroke sensor overlap in a vehicle longitudinal direction, it may become difficult to attach the stroke sensor. Therefore, it is required to design such that an attachment working space of the vehicle-body attachment portion does not interfere with the pedal rotational axis, considering an easy insertion of working tools into the vehicle-body attachment portion of the pedal. Consequently, there is a problem in that the flexibility of design may deteriorate and arranging the stroke sensor may become difficult in a case in which a brake pedal and an accelerator pedal are provided adjacently in a vehicle width direction.
In either case, the design for both ensuring the attachment working space for the vehicle-body attachment portion and avoiding the interference of the pedal rotational axis with the stroke sensor in a pedal falling-off state is required, considering the easy insertion of working tools into the vehicle-body attachment portion of the pedal.
In the meantime, Japanese Patent Laid-Open Publication No. 2013-32115 discloses a structure provided with a falling-off mechanism (falling-off means) to make the pedal fall off the pedal bracket in the vehicle collision, in which the stroke sensor is arranged coaxially with the pedal rotational axis.
This conventional structure disclosed in the above-described Japanese patent document has a problem in that an arrangement position of the stroke sensor may be limited, the assemblability of the pedal and the stroke sensor may be bad, and the flexibility of design may be improperly low.
Further, US Patent Application Publication No. 2010/0313699 A1 discloses a structure in which the stroke sensor is arranged to be offset upward relative to the pedal rotational axis, and a pedal rotation and an input shaft of the strike sensor are connected via a link arm, a link rod, and a sensor arm.
This conventional structure disclosed in the above-described US patent document has a problem in that the serviceability of the stroke sensor may be bad because the stroke sensor is positioned inside the pedal bracket having a U shape in a plan view, and also the layout performance of the stroke sensor may be bad because the stroke sensor is arranged at a deep position located upward and forward relative to the pedal rotational axis. Further, there is a problem in that a sensor swing angle relative to a pedal swing angle is so nonlinear that the degree of asynchronization may become improperly big.
Further, Japanese Patent Laid-Open Publication No. H9-164925 discloses a structure in which an arm portion extending forward from the pedal rotational axis and a rotational element extending rearward from the stroke sensor are interconnected, wherein a pin is provided at a free end of the arm portion and a U-shaped groove is formed at the rotational element.
According to this conventional structure disclosed in the above-described Japanese patent document, since the stroke sensor is positioned inside the pedal bracket having the U shape in the plan view, the serviceability of the stroke sensor may be bad. Furthermore, this conventional structure is not configured to make the pedal rotational axis fall off its support portion when the collision load to make the pedal retreat toward the passenger side is applied to the vehicle body. Additionally, since the rotational element provided on a sensor side and the arm portion provided on a pedal side are arranged straightly along a line passing through the pedal rotational axis and the sensor's rotational center in a state in which the pedal is not depressed, there is a problem in that the degree of asynchronization of the pedal stroke and the rotation of the stroke sensor, i.e., the difference in rotation between the pedal and the stroke sensor, may become improperly big.